Buoyage

IALA Buoyage Regions

 

The world is divided into two buoyage regions by the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA).

 

  • Region A – Covers Europe, Africa, Australia, New Zealand, most of Asia, and the Arabian Gulf. Red marks port and green marks starboard when entering from seaward. (Think: Red to Port when Returning).

 

  • Region B – Covers the Americas, Japan, South Korea, and the Philippines. Here it’s reversed: red marks starboard and green marks port when entering from seaward. (Think: Red Right Returning).

 

All other marks (cardinal, isolated danger, safe water, special, wreck buoys) are the same worldwide.

Lateral Marks (IALA A)

Lateral marks are used to show the edges of a navigable channels, guiding vessels safely into harbours, rivers, and passages. In IALA Region A, red buoys mark the port (left) side of the channel and green buoys mark the starboard (right) side when entering.

 

Port Lateral Mark

 

  • Purpose: Marks the Port Side of a Channel or Fairway
  • Colour: Red

  • Shape: Can (cylindrical)

  • Topmark: Single red can (optional)

  • Light (if any): Red

  • Flash: Any rhythm except composite group flashing 2+1

Starboard Lateral Mark

 

  • Purpose: Marks the Starboard Side of a Channel or Fairway

  • Colour: Green

  • Shape: Conical

  • Topmark: Single green cone, point/apex up (optional)

  • Light (if any): Green

  • Flash: Any rhythm except composite group flashing 2+1

Preferred Channel Marks

IALA A

IALA B

Preferred Channel to Starboard

 

Purpose: Indicates the preferred (main) channel continues to starboard
Colour: Red with a broad green band

Shape: Can, Conical, or Pillar/Spar

Topmark: Single red can (optional)

Light (if any): Red

Flash: Composite group flashing (2 + 1)

Preferred Channel to Port 

 

Purpose: Indicates the preferred (main) channel continues to port

Colour: Green with a broad red band

Shape: Conical, Can, or Pillar/Spar

Topmark: Single green cone, point up (optional)

Light (if any): Green

Flash: Composite group flashing (2 + 1)

Preferred Channel to Port

 

Purpose: Indicates the preferred (main) channel continues to port
Colour: Red with a broad green band

Shape: Conical, Can, or Pillar/Spar

Topmark: Single red can (optional)

Light (if any): Red

Flash: Composite group flashing (2 + 1)

Preferred Channel to Starboard

 

Purpose: Indicates the preferred (main) channel continues to starboard
Colour: Green with a broad red band

Shape: Can, Conical, or Pillar/Spar

Topmark: Single green cone, point up (optional)

Light (if any): Green

Flash: Composite group flashing (2 + 1)

Cardinals 

Cardinal marks indicate the position of a danger, such as a wreck, shoal, or rock, and show the mariner the safest side on which to pass. For example a North Cardinal, indicates not only to stay North of it, but that the danger is to the south. The top marks indicate the location of the black colour section on the buoy.

 

North Cardinal

 

Colour: Black above yellow

Topmark: Two black cones pointing up

Light: White, very quick (VQ) or quick (Q) continuous

East Cardinal

 

Colour: Black with yellow band (black-yellow-black)

Topmark: Two black cones point away from each other (↑↓ like an Egg)

Light: White, Q(3) or VQ(3) – groups of 3 flashes

South Cardinal

 

Colour: Yellow above black

Topmark: Two black cones pointing down

Light: White, Q(6)+Long Flash (LFl) or VQ(6)+LFl – 6 quick flashes + 1 long

West Cardinal

 

Colour: Yellow with black band (yellow-black-yellow)

Topmark: Two black cones point together (↓↑, like an Wine Glass)

Light: White, Q(9) or VQ(9) – groups of 9 flashes

Other Buoys

Special Marks

 

Purpose: Marks special areas/features (cable, recreation, spoil ground, etc.), not for a navigation hazard. 

Colour: Yellow

Shape: Any

Topmark: Yellow "X" (St. Andrew’s cross)

Light (if any): Yellow

Flash: Any rhythm not used for white cardinal or isolated danger

Safe Water Mark

 

Purpose: Safe Water Marks (Sometimes called Fairway buoys) Indicate safe, navigable water all around.

Colour: Red and white vertical stripes

Shape: Spherical, pillar, or spar

Topmark: Single red sphere (optional)

Light: White

Flash: Isophase (Iso), Occulting (Oc), Long Flash (LFl10s), or Morse “Alpha” (· —)

Isolated Danger Mark

 

Purpose: Marks a small danger with safe water all around

Colour: Black with one or more red bands

Shape: Pillar or spar

Topmark: Two black spheres (balls) (The Denis the Menace Buoy) 

Light: White

Flash: Group flashing 2 (Fl(2))

Emergency Wreck Marking Buoy (temporary or new wrecks)

 

Colour: Blue and yellow vertical stripes

Topmark: Yellow cross

Light: Blue + Yellow alternating flashes, 1s each